Wow, it seems they rewrote their AppleScript support which means a re-write of any existing script for it? Seems like a bad choice..
Anyway, the good news is that I have done exactly that so Yummy now automatically detects iTerm 3 and supports it for Open In Terminal

The new version of iTerm has the ability to tell me if a session is busy or not, and I've taken advantage of that in the new script.
So I wonder.. is there any purpose in spending time revising the iTerm2 script at this point?
I'll send out a beta so you can see it in action asap.